Patent GB-839519-A (GB)
Title: Improvements in or relating to railway traffic control systems
IPC: B61L19/06
Filed: 1958-03-06
Abstract: 839,519. Centralized traffic control systems. GENERAL RAILWAY SIGNAL CO. March 6, 1958 [March 20, 1957], No. 7235/58. Class 105. A railway centralized traffic control system in which points and signals are arranged to be controlled in groups includes control designating means common to all the groups and settable to designate the control effect, e.g. stop or clear condition for signals, normal or reverse position for points, to be applied to each points and each signal in a group, group selection means such as press-button switches for. selecting a group of points. and/or signals to be controlled and means for applying the control effect designated by the control designating means to the selected group of points and/or signals selected by the group selecting means. Thus a control panel is divided into a plurality of -similar control sections, and if there are more than one points or one signal per group, the points are allocated to respective control panel sections and the signals are allocated to respective control panel sections. Associated or dependent signals may however be treated as one with the associated signal and a crossover may be treated as one points. Each of the control panel sections is associated with a set of relay control buses subject to selective energization by the control designating means of the panel sections to select code-selecting relays in a bank of relays allocated to a respective group for selecting points and signalcontrol codes for transmission to the points and signals in the chosen group. The groupselecting means permit only one of the relay banks to have its relays controlled by the control designating means of one panel section at a time. Provision is made for points or track blocking to prevent, e.g. inadvertent routing of a train into a stretch of track temporarily out of service for repair or "fleeting " control of a signal which enables that signal which has reverted to stop after a first train has passed to be automatically cleared to allow a following train to pass. Fleeting control, when rendered effective, automatically renders effective the code communication apparatus after each passage of a train past the signal, to communicate a control to clear that signal for governing the passage of another train over the same route. Blocking and fleeting controls are effected by pulling out from positions in which they are normally biased the relevant selfrestoring push-buttons employed for designating controls of the points to be blocked or signal of the track to be blocked or the signal to which the fleeting control is to be applied together with operation of a push-button on the panel section designating the blocking or fleeting function. In the embodiment to be described, the points and signals at the lefthand end of the passing siding A, B, are in Group A and those at the right-hand end are in group B. All the points and signals of the double direction traffic track section C are in group C and include the two cross-overs. This grouping of the points and signals is by field locations as far as the code communication system for the remote control of the points and signals from the central office is concerned, but these groupings need not necessarily correspond to the field location groupings. The track diagram 52 of the track layout is mounted in front of a console type control machine 53 and, as shown in Fig. 8, includes various indicating lamps, associated with the respective track sections and groups of points and signals. The console panel P, Fig. 1, includes a plurality of similar panel sections PS1; PS2, &c., Fig. 4A, for the designation of points and signal controls for communication by a code communication system to the respective groups of points and signals. The group selecting buttons GA ... GE select the group of points and signals to be controlled and other system control buttons FL, MC, SM, LOC are provided. A changeable track group indicator TGK is selectively controlled to display the track layout of any designated group for which the controls are intended and is adjustable to the line of sight of an operator seated in front of the control console 53. In this embodiment illustrated in Figs. 4A, 4C, code-selecting magnetic stick relays are used but the Specification also describes an embodiment (Figs. 7A and 7B, not shown), in which neutral relays having stick circuits are used for selecting the code to be transmitted to the points or signal under control. To control the group B, for eastbound traffic, i.e. left to right, for example, the operator depresses the group selection button GB and causes the track group indicator TGK to be illuminated to display the track diagram relevant portion and an indicator lamp BGE3 lights to indicate the group that has been selected, as well as indications on the track diagram, Fig. 8. The operator then operates the control buttons on the respective panel sections PS1, PS2, &c., Fig. 2, corresponding to the points and signals. For example, to operate points No. 1, the button 1NB or 1RB, Fig. 4A, would be operated, depending upon the desired normal or reverse position of the points No. 1. Should a second points in the group have to be controlled, then the buttons 2NB or 2RB on panel section PS2 would have to be operated and so on, each points of a group being associated with its respective panel and likewise the signals if there be more than one signal, the buttons 1SGB, 2SGB, &c. are operated. The buttons WGB, EGB are used for west-bound or east-bound traffic respectively and the start button SPB is operated when the selection of the codes for points and signals is complete, to start a cycle of transmission of the relevant codes by the communication apparatus, Fig. 2. On depressing button GB, Fig. 4A, the group B code selecting relay bank, Fig. 4C, is made responsive to energization of the first switch and signal buses in accordance with the actuation of the points and signalcontrol buttons on the panel section PS1. The group selecting apparatus includes a relay LOS, Fig. 4B, which provides that only one group selector relay LOP, can be picked up at any one time and this group interlock is maintained until the designated points and signal controls for the group that have been designated have been transmitted to the field, or until a cancellation button is actuated to cancel the group designation. Relay B-LOP, Fig. 4C, is picked up over a circuit from (+) b.c. 60 LOS (back contact 60 of relay LOS), b.c. 61 button GA (unoperated position), wire 62 f.c. (front contact) 63 of button GB (operated position) winding of relay B-LOP, b.c. 64 B-1CH, bus wire 65, b.c. 66 of group cancel button LOC, Fig. 4A, to (-). Relay LOS is picked up over f.c. 67 B-LOP to open the pickup circuit of relay B-LOP at b.c. 60 LOS so as to prevent any other LOP relay picking up. Relay B-LOP is held over its own front contact 680. On picking up relay B-LOP, at its front contacts, connects the relays of the code selecting relay bank B1, Fig. 4C, belonging to the Group B to control buses belonging to the set of buses, as shown associated with the panel section PS1. The operator then designates the required position of the points, e.g. by pressing button 1RB of panel section PS1, Fig. 4A, for the reverse position of the points 1 to pick up relay B-1CWP over a circuit from (+) f.c. press contact 69, button 1RB, wire 70, f.c. 71 B-LOP, b.c. 73 B-1BWP (points blocking relay), winding of relay B-1CWP to battery centre tap (C); on depression of button 1NB for the points to be in the normal position, relay B-1CWP would have been energized with reverse polarity (corresponding to position shown). For east-bound traffic the control signal at station B is cleared by pressing the signal button 1EGB to pick up the relevant code-selecting relay B-1EGP, Fig. 4C, over the circuit from (B+) f.c. 74 button 1EGB, wire 75, f.c. 76 B-LOP, b.c. 77 B-1EBP, b.c. 78 B-1WGP and winding of relay B-1EGP to (C). On picking up, relay B-1EGP selects (Fig. 5A, not shown), a signal clearing code for transmission to the signal: in the field. For the reverse direction of traffic depression of button 1WGB picks up relay B-1WGP to select an appropriate signal code for clearing the westbound traffic signal at station B. The operator now actuates the start button 1SPB, Fig. 4A, to pick up the relay B-1CH, Fig. 4C, over a circuit from (+), f.c. 79 of button 1SPB, wire 80, f.c. 81 B-LOP upper winding of relay B-1CH, to (-) and this relay is held over its front contact 82. At b.c. 64 B-1CH relay B-LOP is de-energized and drops away, but the magnetic stick relays of the associated bank B1 of code-selecting relays are maintained in the last-operated positions. When the code communication system is available for the transmission of the controls that have been designated, relay B-1LC becomes picked up over a circuit, including back contacts of stepping relays of a code communication system and back contacts of relay CH of other groups, wire 92, f.c. 93 B-1CH, b.c. 94 B-LOP, b.c. 95 B-1TXB (automatic start relay) and the upper winding of relay B-1LC to (-) and is maintained energized by its second winding by a stick circuit over its front contact 104 and wire 103 and front contacts of the said stepping relays until the end of a cycle of operation of the communication system. At f.c. 108 B-1LC relay B-1CH is dropped away since the lower winding of relay B-1CH is energized with reverse: polarity compared to that of the stick circuit over a circuit (+), a front contact of a relay of the communication system, wire 106, f.c. 107 B-1CH, lower windings of relay B-1CH, f.c. 108 B-1LC, wire 109, b.c. 110 A-1LC, Fig. 4B, to (-). The picking up of relay B-1LC connects contacts (Fig. 5A, not shown), of the codeselecting relay bank to the code-communication stepping channel wires to determine the station code to be transmitted and in like manner operation of but